低転位GaN 基板上縦型HFET

摘要

A novel vertical heterojunction field-effect transistors (VHFETs) with re-grown AlGaN/GaN two-dimensional electron gas channels on low dislocation density free-standing GaN substrates have been developed. The VHFETs exhibit a specific on-resistance of 7.6 mΩcm~2 at a threshold voltage of -1.1 V and a breakdown voltage of 672 V. The breakdown voltage and the figure of merit are the highest among those of the GaN-based vertical transistors ever reported. It was also demonstrated that the threshold voltage can be controlled by the thickness of AlGaN layers and a normally-off operation is achieved.%再成長AlGaN／GaNの2次元電子ガスをチャネルとする低転位GaN基板上の縦型Heterojunction Field-Effect Trasistor（HFET）を開発した．縦型HFETの特性オン抵抗は7.6m Ωcm~2，しきい値電圧は-1.1V，耐圧は　672Vであった．これらの値は，これまで報告のあったGaN系縦型トランジスタを上回る性能指数となる．さらに，AIGaN膜厚の最適化によりノーマリオフ動作が可能であることを確認した．